Valve bag with pasted end closure



June 23, 1959 H. E. LEE

VALVE BAG wma PASTED END cLosuRE Filed March 9, 1956 JNVE'NTOR. H4 P/PVELEE.

///l// l llllttll ZW//Mmhm United States- Patf O VALVE BAG WITH PAsrEDEND cLosUREl v Harry E. Lee, Pensacola, Fla., assignor to St. RegisPaper C0mpany, New York, N.Y., al corporation of, New

York Y v v r v This invention relates to valve bags of the type havingan end closure formed of pasted flaps, that is to say, with an inturnedcorner flap at each corner and with overlying side flaps pasted` withrespect to one"corner ap, and with a valve opening provided between theother corner flap and the overlying side aps." Such bags are formed ofpaper or the like sheet material which may sometimes be laminated with'other material to reinforce same orV to render same moisture-proof or.capable of resisting deterioration by reason of chemically activematerials contained in the bag. Usually,.but not necessarily, the bagsof this invention are formed of a plurality of plies of the sheetmaterial.. f- Y -v It has ofter1.been.thelpraticey to ,insert a flexiblesleeve or supplemental sheet 'inmth'e' valve'of such bags to extendinwardly beyond the valvetlip at thefinner end ofv the-corner.' ilap sothat suchvsleeve or sheetwilllbe collapsed or` pressed bythe contents`of the'bag. ;wl1en filled up against the interior of the top of the bagfor more securely closing thefvalvefaga'inst leakage and sifting out,ofythe contents. It basalso been the practice so to secure' such4 sleeve'or supplemental' sheet to th'e lvalve lip that the latter will be thrustup against the top of the bag along with the sheet or sleeve. Despitenumerous different expedients of this nature which have been used toobtain more secure and dependable closing of such valves, it is possiblefor some material, particularly if of a granular nature, to sift out.While this can largely be overcome by providing an outwardly protrudingsleeve adapted to be tucked into the Valve after filling the bag, yetsuch tuck-in type sleeves have to be carefully and manually tucked in bythe workman who operates the automatic filling machine and thissubstantially reduces the speed and increases the cost of filling thebags.

With the present invention, the above difficulties are quitesurprisingly and effectively overcome by using an inwardly directedvalve sleeve so secured in place in the valve that in effect a pocketwill be provided between the inner portions of the valve lip andportions of the sleeve material thereabove which are thrust up againstthe top of the bag when filled. Such pocket has its open end directedinwardly of the bag and thus when the bag is illled and bounced oif fromthe filling machine spout, the material in the bag will thrust thegreater part of the sleeve firmly up against the inside of the top ofthe bag, for effectively collapsing and closing the sleeve, and a massof such material will be thrust into such pocket, such mass preventingthe valve lip from being pushed up along with the collapsed sleeve andserving in effect as a wedge between the valve lip and the collapsedsleeve portions thereabove and acting thereafter to hold the outerportions of the sleeve collapsed in secure valve-closing condition.

If at least portions of the valve lip of such a construction are maderelatively stiff as by pasting a plurality of plies thereof togetherwithout pasting same with respect to the collapsible sleeve portionsthereabove,

p 2,891,716 `Paten-ital- ,Jurrie "23 1959 Vice then the closing effectdue to such pocket will be espe# cially effective. l i i Preferably thesleeve in accordance with the inve'n tion is made at1its outer end'pwitha folded-,over'portion f orrningan inwardly directed cuff andl,theouter,surface of this culi is pasted to thetinside wall surfaces inthe valve opening sothat the pocketvforms betweensuch cuff and theadjacent portions of the sleeve per-se; The material ofsuch cuff at thisinner end may, if desired, be'continued'and folded outwardly to theouter end of the sleeve and thence again inwardly inside the sleevefor'somefdstance whereby theouter portions'fof the pocket will have atleast' two plies.

`Other and more specific objects, features and fadvn'- tages Aof theinventionwillappear from the detailed description given below, taken inconnection Awithftlna accompanying drawings which forrn- `a part .of`this specification and illustrate by way of examplethe presentpreferred embodiment of the invention. Iny the drawings: v t v v. Fig. 1is a perspectveview of thevalve' corner of a Vbag made in accordancewith the invention;Y r Figs, 2 and 3 respectively are fsectionalwiews,taken substantially alonglines 2 2 audit-3y ofFig.1; yand Fig.` 4 is' aperspective view ,of a preferred forni', of sleeveadapted for use inaccordance'gwith theinvention. Referring now to Fig. ,1i in furtherdetail, a .multiwallxbag is here shownat 10 lhavingan; intlllrned'vaglvecorner flap 11,`with overlying side ilapsf'of conventional `'formasatl12 and 13. The valve 'sleeve is indicatedat 14 and shown inv further,ydetail@beforedts insertion in .Fig- 4. p A s' shownin Fig'. y4,'.theNsleeve may comprise adlttened Vtubular `feleniert fc'ir'rnefdat itsouter-fend with Qa folded:- Qvf;p' fris, whenitinsefd 'meeba-isfdass@inwardly f' the vane. The-upper sufefof' the can and under surface areasas at 16 insofar as same contact with the corner or side flaps in thevalve, are adapted to be pasted to the latter. The areas on the insideof the cuif are free from pasting to the sleeve per se, so that a pocketopening inwardly of the bag is formed as indicated in Figs. 3 and 4. Thesleeve may be formed by taking a suitable area of sheet material andfolding it over to form the flattened tube as shown and with thefolded-over edges overlapped and glued together as at 17 (Fig. 2). Thesurface of the sleeve which is to be the undersurface of the inner endthereof in the bag, may, if desired, be slit as indicated at 17a, suchslit as shown being at a slightly angular position permitting the edgesof the slit to overlap somewhat without wrinkling in case pressure isapplied to the upper face areas of the filled bag tending to compressthe sleeve edgewise. Various other forms of slits well known for suchvalve sleeves may be used, if desired. While ordinary at kraft paper maybe used as the sleeve material, in some cases it may be preferred to usea relatively llexible laminate of two thin sheets of paper for examplewith a thin interposed asphalt layer therebetween or a sheet of papercoated with a film of polyethylene or other moisture-proof material maybe used as is well understood in the art of manufacturing bag valvesleeves.

The sleeve may be inserted in the bag valve during the operation ofbottoming the bag by the same type of automatic operations heretoforecustomary for inserting sleeves in pasted end bags. That is to say, thecui 15 in this case may have adhesive applied thereto or the bag apsurfaces which are to contact with the cuif may have suicient adhesiveapplied thereto so that when the sleeve is put into place, it willremain lodged with its outer end affixed and sealed with respect to theinside wall portions of the Valve. Bags in accordance with the inventionmay be lled on automatic filling machines in .the same manner asheretofore accomplished simply by placing the bagon 'the'fillrig spoutof the machine with the spout extending into the' sleeve. And when thebag is lled and is dropped oi or bounced from the region of the llingspout Onto a 'conveyor for example, ,the material in thebag will bethrust up'agains't "theinterior of the top of the bag causing the innerportions of 'the sleeve to become collapsed as indicated' 'at'20 in Eig.'3. This will cause the upper e'nd of the bag to arch 'upwardly Somewhatincluding the portions as at 21 which "are located above the valve 'lipshown at 22 in Figi 3. Consequently a pocket as indicated will be formedinto which a 'mass of the material will immediately lind itsway,`thereafter acting in effect like a wedge preventing the valve lip'22 from llexing' upwardly and keeping the sleeve portions as at 2.1firmly collapsed even to the outermost portions as at A23 which will beexposed outside the valve. 'It would normally be expected that when thematerial inthe bag `forces the inner portions of the sleeve up Ytocollapsed condition, the valve lip 22 would similarly be forced upagainst the top of thev bag, thus preventing the opening of any pocketfor the reception of material as above described, `In fact heretofore sofar as is known, it has been the universal practice so to secure thevalve sleeves in such valves as to insure that the valve lip areas wouldbe pulled or forced up against the top of the bag, it having beensupposed that such a result was essential to good closing action of thevalve. However, extensive tests have shown quite surprisingly that ifthe sleeve is so ksecured as above explained as to permit the pocket tobe formed, then invariably the pulverulent or granular' material' in thebag will enter and more or less lill 'such pocket and therefore ajo'rdthe above-explained wed'g'in'g 'effect forV firmly collapsing' andclosing even the outermost 'portions' of' the sleeve.

Although a preferred embodiment of the invention is herein"disclosed'vfor purposes of'explanation, V'various modifications'thereof, after study of this "specification, inayY be apparent to thoseskilled in the art to which the georgia i invention pertains. Referenceshould accordingly be had to the appended claim in determining the scopeof the vti., .i

What is claimed and desired to be secured by Letters Patent is:

ln a valve bag of the type having an end closure formed of corner apsand adhered overlying side aps and with one of the inturned 'underlyingcorner aps forming a valve lip, said side aps joining with corner flapsalong diagonal foldlines, a sleeve positioned in the 'valve and normallyatwise against the 'inside of the top of the bag when empty, 'suchsleeve vhaving flexible portions protruding inwardly of the bagsubstantially beyond such lip and adapted to be pressed up against theinside of the top of the bag by material therein when filled, the outerend portion of the sleeve vbeing formed with a cuff directed inwardly ofthe bag, a part of the culled portion of the sleeve extending outwardlyof the bag corner in exposed position beyond said diagonal fold lines,exterior portions of said cut being secured and sealed with respect tothe interior walls of the valve, a pocket thereby being providedV whenthe bag is lilled, between the cul and 'other portions of the sleevewhich are adapted to arch upwardly together with the top vof the bag,such pocket being open to the interior of the bag for receiving a massof the material filled therein, whereby such mass will retain the sleeveportions thereabove up in collapsed valve-closing condition and with thevalve lip portions spaced therebelow.

References Cited in the le of this patent STAEES PATENTS 2,040,335-Rosmait May l2, 1936 2,275,505 Crawford Mar. 10, 1942 2,590,568 PetersMar. 25, 1952 PORElGN PATENTS

